On small screen virtual keyboards normally tiny keys are hard to see and accurately select, make typing slow, tedious, difficult, and highly error prone. Tedious and inaccurate text entry can also be a significant problem even on larger devices such as tablet computers when typing on a virtual keyboard.
Virtual keyboards typical of touch screen mobile devices are also challenging to use because they generally duplicate the design of larger physical desktop keyboards, not taking into account the different ergonomics of small screen virtual keyboards, particularly common hand held usage. The mobile devices of interest in this invention are typically smartphone-type handheld computers, such as the Apple iPhone devices, Android devices, or similar sized devices that are typically about 60-70 mm wide and 100-140 mm long, typically small enough to fit in a pant, shirt or jacket pocket. but other larger or smaller devices can also be used with this invention. For example wrist worn devices or tablet computers. These handheld computers can be used to prepare and send SMS text messages, emails, and edit word processing documents. There are many other applications on such handheld computers that require text input, for example entering web addresses, and usernames and passwords. The aforementioned handheld computers typically display a virtual keyboard when text entry is required, usually splitting the screen between an upper portion displaying content, and a lower portion displaying a virtual keyboard.
In common usage, one or both hands are typically used to cradle and hold the mobile device, and the user taps the keyboard with their thumbs, resulting in “thumb typing” on keyboards designed for 10 fingers. Virtual keyboards optimized for thumb typing has been described previously, for example in European patent publication EP2194437, and US patent publication US2013/0057475.
Various ergonomic improvements disclosed in the prior art involve variable keyboard positioning, such as centering on the device, and split keyboards, designed to move keys closer to fingers, particularly the thumbs, at the edges of the device. The Apple IPad variable keyboard is a commercial example of these two approaches.
But even with such improvements, typing on virtual keyboards remains more awkward and difficult than necessary, often because the keyboard layout remains the static QWERTY standard of physical keyboards. There have been many efforts to improve on the QWERTY layout, for example the Dvorak design which re-positions keys based on letter frequency; however few if any address the specific needs of the virtual screen mobile typing. Furthermore, many Dvorak-like designs are so different from the QUERTY standard that adoption is fairly limited, as users prefer to stick with just one standardized, if less than optimal, keyboard layout.
Virtual keyboards are a text input user interfaces employed on computer screens in which the computer renders an image of a keyboard, and the user selects “keys” directly from key images, where a “key” is nothing more than a selectable screen region. Virtual keyboards generally lack physical keys and rely on touch screens in which direct user finger or stylus touch selects keys. Other types of virtual keyboards can involve myriad selection methods, such as pointer devices like mice, hand gesture movement sensors, eye movement tracking, even direct nerve impulses or thoughts using biosensors.
Some inventions optimize the ergonomics of thumb typing by customizing keyboard dimensions and layouts to individual thumb and hand sizes. An example is seen in US 20130057475 A1, “Split keyboard for thumb typing”.
Another common approach improves thumb typing ergonomics with keyboard layouts that conform more closely to the easiest thumb movements, generally involving an arcing motion with thumbs loosely extended and tip unbent. Examples can be seen at www.blog.42at.com/thumb-keyboard-concept-for-the-ipad. However, such designs tend to significantly after common and popular desktop designs, requiring learning entirely new layouts, with steep learning curves, a big drawback for many users.
Another approach to making small virtual keyboards easier to use is word completion menus. One such method is disclosed in U.S. Pat. No. 7,886,233, (the 233 patent) involving text typing triggered menus which try guess the completed endings of words being entered.
Another approach is to make the most important keys larger in size and more visible, seen in software products like ThickButtons (www.thickbuttons.com) supported by provisional U.S. Pat. No. 8,413,066, US20100115448.
“Sloppy” typing is a common and effective enhancement method which permits imprecise but automatically corrected typing, using predictive analysis to figure out which letter was actually intended.
However even the most effective enhancement approaches have significant limitations on the smallest screens, since most adhere to conventional keyboard paradigms, such as always displaying the entire set of static, single letter keys. This results in too many keys in too small a space, making them very challenging to see and accurately select. For example, sloppy typing slows down greatly the more keys the user simultaneously touches. And visualization problems become even more challenging for the visually impaired and older people.
Conventional word completion menus also become challenging to use efficiently on the smallest screens because of inadequate space to display and easily see multiple full length word suggestions.
A different approach is shown in co-pending patent applications PCT/US2014/31121 and US2014/776,742 titled “Space Optimizing Micro Keyboard Method and Apparatus”, which discloses limited menu key sets based on prioritized letters and small incremental word completion fragments, allowing fewer, but larger than normal, variable key sizes, improving usability on very small screens. This approach effectively transforms the keyboard into a partial word completion menu system, while also retaining standard, layouts like QWERTY, particularly the familiar patterns of the relative positions of letters and keys; this allows the user to quickly find keys in the same locations as their normal desktop keyboard.
However, none of these advanced word completion approaches specifically addresses ergonomic thumb typing optimization needs.
What's needed are better virtual keyboard layouts specifically addressing the common ergonomic usage patterns of virtual keyboard thumb typing, particularly on very small screens.